Help!!!! Broken Threads On Cases!

[greg78gs750]

well, now i am a little frustrated. pulled off the rt. side cover, cleaned and polished it, lubed the clutch adjuster etc, and when i put it back on, SNAP. or, more like, pwah. well, on inspection, the po had repair some of the threads in here with some crappy welding. i am talking about the threads on the engine case that the sprocket cover threads into, specifically the 2 screws inside the throttle adjuster cover.

my question is this: how do i fix it?? do you think i could form a new bit with some jb weld, drill and tap it? splitting the cases, or further disassembly is NOT HAPPENING. i really want to ride this motorcycle. this project started as a fairly simple carb cleaning that (inevitably) turned into more. i really dont think i could get a good weld with the thing together, as i am pretty sure that is what was attempted before. help, guys. how much stress can threaded jb weld take?

i would post some pics of this debacle, but i have a dial up connection and it is not working well today anyway. i am pretty frustrated here, any advice would be appreciated.

thanks.

greg

[Dogma]

Is there not enough metal left for an insert of some kind?

[catbed]

if its the sprocket cover, you could use some jb weld, since it doesnt hold anything back, just a cover.

[chef1366]

Heli-coil it.

[Nessism]

Heli-coil it.

Agree! :-D:mrgreen:8)

[greg78gs750]

ok. helicoil. sure. sounds good. except.....it isnt so much that the threads are stripped, as the little "nipple" of metal holding the threads has broken away. but, i think i have formulated a plan of action. i think i am going to helicoil it.....haha....i think i will insert the helicoil in the threads that remain, then build up around it with some jb or other such epoxy product. the think that concerns me most is that this sprocket coverr holds the clutch adjuster/actuator, and i think?/ this has to be held fairly...firmly to push the clutch plates apart.....any ideas on this? geez, i need high speed.....

thanks guys!

[catbed]

i see how it is guys.

BTW the way, sprocket cover is on #1 cylinder side, clutch cover is on the #4 side.

[greg78gs750]

ok, right, well, it is the sprocket cover. but this holds the clutch adjuster/actuator. so.....anyway. upon further review, i do have some questions. i guess i am going to have to apply the jb first, then drill tap and coil that, since the coil needs to compress....so building the epoxy around the coil wont really work. also.....the holes bottom, which makes me wonder if tap will work, in terms of cutting threads in far enough into the hole. i know they make taps to cut threads in bottoming holes, but.....rrrrrrr. nothing is easy, is it? any additional wisdom would be much appreciated.

[earlfor]

It appears you have never installed a helicoil. You will need to drill out the hole with the precisely correct size drill bit for the helicoil. (Usually in helicoil kits, included is the correct bit, the tap and a special tool for setting the helicoil) You drill the damaged hole to the correct diameter, then you use the tap and thread the hole. this fits the OUTSIDE diameter of the helicoil. The installation tool fts inside the helicoil and you then turn the helicoil into the threads you cut. The tool then turns out (is removed) and the the new bolt will now thread into the inner threads of the helicoil.
You might say, a helicoil is a threaded thread. It has threads on both sides.
There is no compressing it on installation. It threads in.

Earl

ok, right, well, it is the sprocket cover. but this holds the clutch adjuster/actuator. so.....anyway. upon further review, i do have some questions. i guess i am going to have to apply the jb first, then drill tap and coil that, since the coil needs to compress....so building the epoxy around the coil wont really work. also.....the holes bottom, which makes me wonder if tap will work, in terms of cutting threads in far enough into the hole. i know they make taps to cut threads in bottoming holes, but.....rrrrrrr. nothing is easy, is it? any additional wisdom would be much appreciated.

[psyguy]

since you re missing a part of the hole id use a time-sert, not a heli-coil
time-sert is a solid threaded insert (and not only a coil), so i think should suit your situation better

(a pic would be most helpful in getting the diagnosis correct though)

[chef1366]

since you re missing a part of the hole id use a time-sert, not a heli-coil
time-sert is a solid threaded insert (and not only a coil), so i think should suit your situation better

(a pic would be most helpful in getting the diagnosis correct though)

Good idea!

[psyguy]

Good idea!

hey, always a pleasure to get your idea backed up by someone in-the-know :-D
cheers

[greg78gs750]

It appears you have never installed a helicoil. You will need to drill out the hole with the precisely correct size drill bit for the helicoil. (Usually in helicoil kits, included is the correct bit, the tap and a special tool for setting the helicoil) You drill the damaged hole to the correct diameter, then you use the tap and thread the hole. this fits the OUTSIDE diameter of the helicoil. The installation tool fts inside the helicoil and you then turn the helicoil into the threads you cut. The tool then turns out (is removed) and the the new bolt will now thread into the inner threads of the helicoil.
You might say, a helicoil is a threaded thread. It has threads on both sides.
There is no compressing it on installation. It threads in.

Earl

ok. yes, i have never used a helicoil before. the kit i picked up is, in fact, a fix-a-thred, which, while probably inferior in quality to a helicoil, seems to be a similar product.

i quote from the instructions "the inserts are designed to be greater in diameter than the tapped hole. The insert compresses during installation, expands radially and axially and anchors into the tapped hole".

this is accompanied by a picture of the spring being compressed into the hole.

i didnt make that up....

anyway, a timesert seems like it might work better, but i anticipate trouble finding them locally, and the cheapest i could find on the net was $80! without shipping. so, ahead i forge, and if i f it up too much i will just have to take it into the shop and fire up the tig.

thanks guys!!

[greg78gs750]

[greg78gs750]

success!!!! on the photo posting....the offending hole is the one that is, well, broken, there, above the gear indicator sensor and to the left of the shaft.